Issue
Looking for a way to monitor the general overall heath of an IO module in the backplane.

Product line
Modicon 340, Modicon X80, Control Expert, Unity Pro

Resolution
Yes, you can monitor the health of an IO module. Unity offers %SW160 - %SW163 for this purpose.
Each bit within the word will represent a module location along the bus. For example %SW160.3
would contain the health status of rack 0, slot 3. If the bit value is "1" the module is healthy, if the bit value is "0" the module is unhealthy. Each of the remaining %SW's in this group of 4 represent
expansion backplanes.